Kazoologist--one
who studies the kazoo in one or more of its fascinating
fields.

What is a kazoo?

The
properties of a kazoo that I consider most important are:

1)
It has one or more vibrating surfaces which amplifies and
distorts the sound of the player's voice.

2)
The pitch is controlled by the pitch of the player's voice rather
than the length of the air column being altered by slides, fingering,
etc.

Kazoos
are generally considered to be membranophones, with a separate membrane
attached to the body.

Conditions
1
and 2 also apply to instruments that might not be considered
membranophones, in that instead of a separate membrane, the
vibrating
surface(s) consist of part or whole of
the entire body of the device,
being one of the following:

Checking
on the US patents that specifically refer to their invention as a
"kazoo"
I find that they all can be considered to have tubular bodies and
a
separate membrane attached to the body (either internally or
externally).

So what
are the other instruments? I recommend the term kazoid.

Kazoo with the addition of the suffix -oid

Of similar form to, but not the same as. Having the
likeness of. Suffix appended to various words to make an adjective
form.